The role of B_2O_3 in the viscosity and structural variations of CaO-SiO_2-MgO-Al_2O_3-BaO-B_2O_3 slag melt was examined using the rotating cylinder method, Raman spectroscopy, and 27Al and ~(11)B magic angle spinning nuclear magnetic resonance (MAS-NMR) spectra. The results showed that the viscosity of the slag decreased constantly with an increment in the B_2O_3 content although the polymerisation degree of slag enhanced. The addition of B_2O_3 induced the transformation from Q~0 and Q~1 units to Q~2 and Q~3 units in the Si-related structure. The concentration of [AlO_4] structural units increased while that of [AlO_5] and [AlO_6] units decreased. ~(11)B MAS-NMR spectra revealed that [BO_3]-trihedral units with a two-dimensional (2D) structure dominated the B-related structural units. The structural analysis confrmed the decrease in strength and stability of the entire network structure had a more signifcant effect on the viscosity of the slag due to the addition of B_2O_3.
展开▼
